Withania somnifera, known commonly as ashwagandha, Indian ginseng, poison gooseberry,  or winter cherry, is a plant in the Solanaceae or nightshade family. Several other species in the genus Withania are morphologically similar. Although commonly used as a medicinal herb in Ayurvedic medicine, there is no conclusive clinical evidence that it is effective for treating any ailment.

Ashwagandha is commonly used for stress. It is also used as an "adaptogen" for many other conditions, but there is no good scientific evidence to support these other uses.